20D f2.8 focusing [in]accuracy

Started Nov 11, 2004 | Discussions thread
pleal
New MemberPosts: 17
Like?
Re: 20D f2.8 focusing [in]accuracy
In reply to Martin Eager, Nov 12, 2004

I have a 24-70 2.8L and a 70-200 2.8L and both have focusing problems at 2.8, specially with minimum focal range. In fact is also happens with the 17-40L .

PLeal

Martin Eager wrote:

I have a 20D and up until now have had no problems with focusing
with Canon 17-40 f4L and Canon 28-135IS.

Today I received my new Canon 100mm f2.8 Macro and focus is awful.
It front focuses terribly, both at macro range and especially at
telephoto range (and yes I've tried switching between the different
focus distance ranges, used centre point AF and made sure I'm not
inside the minimum focusing distance etc).

This is my first f2.8 lens. The 20D is supposed to have increased
focus accuracy with f2.8 lenses and better. Since my 20D focuses
fine with non f2.8 lenses but ironically not with this f2.8 lens,
is it possible that my 20D has a fault when it steps up to the more
accurate focus sensors? Or is it more likely just a faulty lens?

The lens will be going back for exchange or refund anyway, but it's
now got me worrying if I'll have problems with other f2.8 lenses.

Getting really tired of poor Canon quality control.

Martin
http://photos.runic.com

Reply   Reply with quote   Complain
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark post MMy threads
Color scheme? Blue / Yellow